source: rtems/c/src/lib/libbsp/powerpc/gen83xx/startup/bspstart.c @ 574fb67

/**
 * @file
 *
 * @ingroup mpc83xx
 *
 * @brief Source for BSP startup code.
 */

/*
 * Copyright (c) 2008
 * Embedded Brains GmbH
 * Obere Lagerstr. 30
 * D-82178 Puchheim
 * Germany
 * rtems@embedded-brains.de
 *
 * The license and distribution terms for this file may be found in the file
 * LICENSE in this distribution or at http://www.rtems.com/license/LICENSE.
 *
 * $Id$
 */

#include <string.h>

#include <rtems/libio.h>
#include <rtems/libcsupport.h>
#include <rtems/score/thread.h>

#include <libcpu/powerpc-utility.h>

#include <bsp.h>
#include <bsp/irq-generic.h>
#include <bsp/ppc_exc_bspsupp.h>

#ifdef HAS_UBOOT

/*
 * We want this in the data section, because the startup code clears the BSS
 * section after the initialization of the board info.
 */
bd_t mpc83xx_uboot_board_info = { .bi_baudrate = 123 };

/* Size in words */
const size_t mpc83xx_uboot_board_info_size = (sizeof( bd_t) + 3) / 4;

#endif /* HAS_UBOOT */

/* Configuration parameters for console driver, ... */
unsigned int BSP_bus_frequency;

/* Configuration parameters for clock driver, ... */
uint32_t bsp_clicks_per_usec;

static char *BSP_heap_start, *BSP_heap_end;

/*
 *  Use the shared implementations of the following routines.
 *  Look in rtems/c/src/lib/libbsp/shared/bsplibc.c.
 */
extern void cpu_init( void);

void BSP_panic( char *s)
{
        rtems_interrupt_level level;

        rtems_interrupt_disable( level);

        printk( "%s PANIC %s\n", _RTEMS_version, s);

        while (1) {
                /* Do nothing */
        }
}

void _BSP_Fatal_error( unsigned n)
{
        rtems_interrupt_level level;

        rtems_interrupt_disable( level);

        printk( "%s PANIC ERROR %u\n", _RTEMS_version, n);

        while (1) {
                /* Do nothing */
        }
}

void bsp_pretasking_hook( void)
{
        /* Initialize libc including the heap */
        bsp_libc_init( BSP_heap_start, BSP_heap_end - BSP_heap_start, 0);
}

void bsp_calc_mem_layout()
{
        size_t workspace_size = rtems_configuration_get_work_space_size();

        /* We clear the workspace here */
        Configuration.do_zero_of_workspace = 0;
        /*
        TODO
        mpc83xx_zero_4( bsp_workspace_start, workspace_size);
         */
        mpc83xx_zero_4( bsp_interrupt_stack_start, bsp_ram_end - bsp_interrupt_stack_start);

        Configuration.work_space_start = bsp_workspace_start;

        BSP_heap_start = (char *) Configuration.work_space_start + workspace_size;

#ifdef HAS_UBOOT
        BSP_heap_end = mpc83xx_uboot_board_info.bi_memstart + mpc83xx_uboot_board_info.bi_memsize;
#else /* HAS_UBOOT */
        BSP_heap_end = bsp_ram_end;
#endif /* HAS_UBOOT */
}

void bsp_start( void)
{
        ppc_cpu_id_t myCpu;
        ppc_cpu_revision_t myCpuRevision;

        uint32_t interrupt_stack_start = (uint32_t) bsp_interrupt_stack_start;
        uint32_t interrupt_stack_size = (uint32_t) bsp_interrupt_stack_size;

        /*
         * Get CPU identification dynamically. Note that the get_ppc_cpu_type() function
         * store the result in global variables so that it can be used latter...
         */
        myCpu = get_ppc_cpu_type();
        myCpuRevision = get_ppc_cpu_revision();

        /* Determine heap and workspace placement */
        bsp_calc_mem_layout();

        cpu_init();

        /*
         * This is evaluated during runtime, so it should be ok to set it
         * before we initialize the drivers.
         */

        /* Initialize some device driver parameters */

#ifdef HAS_UBOOT
        BSP_bus_frequency = mpc83xx_uboot_board_info.bi_busfreq;
#else /* HAS_UBOOT */
        BSP_bus_frequency = BSP_CLKIN_FRQ * BSP_SYSPLL_MF / BSP_SYSPLL_CKID;
#endif /* HAS_UBOOT */

        bsp_clicks_per_usec = BSP_bus_frequency / 4000000;

        /*
         * Enable instruction and data caches. Do not force writethrough mode.
         */

#if INSTRUCTION_CACHE_ENABLE
        rtems_cache_enable_instruction();
#endif

#if DATA_CACHE_ENABLE
        rtems_cache_enable_data();
#endif

        /* Initialize exception handler */
        ppc_exc_initialize(
                PPC_INTERRUPT_DISABLE_MASK_DEFAULT,
                interrupt_stack_start,
                interrupt_stack_size
        );

        /* Initalize interrupt support */
        if (bsp_interrupt_initialize() != RTEMS_SUCCESSFUL) {
                BSP_panic("Cannot intitialize interrupt support\n");
        }

#ifdef SHOW_MORE_INIT_SETTINGS
        printk("Exit from bspstart\n");
#endif
}

/**
 * @brief Idle thread body.
 *
 * Replaces the one in c/src/exec/score/src/threadidlebody.c
 * The MSR[POW] bit is set to put the CPU into the low power mode
 * defined in HID0.  HID0 is set during starup in start.S.
 */
Thread _Thread_Idle_body( uint32_t ignored)
{

        while (1) {
                asm volatile (
                        "mfmsr 3;"
                        "oris 3, 3, 4;"
                        "sync;"
                        "mtmsr 3;"
                        "isync;"
                        "ori 3, 3, 0;"
                        "ori 3, 3, 0"
                );
        }

        return NULL;
}